Metal complex catalysts with hydrazide ligands have in generally been described as oxidation catalysts, for example, in DE 196 39 603. However, the compounds disclosed are not active enough.
In WO 2009/124855 metal complex compounds having hydrazide ligands, preferably with electron withdrawing groups adjacent to the acyl group are described. The respective acylhydrazone ligands and their use are also described. The instant compounds differ from those described in WO 2009/124855 by being substituted with a specific cyclic ammonium group adjacent to the acyl group. This specific substitution pattern ensures a significantly higher bleaching activity as compared to prior art complexes or ligands.
The instant compounds are used especially for enhancing the action of H2O2 or peroxides, for example, in the treatment of textile materials, without at the same time causing any appreciable damage to fibres and dyeings. There is also no appreciable damage to fibres and dyeings if these compounds are used in combination with an enzyme or a mixture of enzymes.